International Journal of Intelligent Engineering and Systems

8

Authors: Peng Shang, Anping Xu, Jingjing Zhao

Recently the steel wire reinforced composite pipelines are increasingly used in many different fields with researches usually focus on their mechanical properties. A constitutive model of the composite pipe’s mechanical properties is presented, which can be used to solve the problems of stress, strain and displacements. After that, 3D CAD models of two kinds of steel wire reinforced composite pipes are built, and then the displacements and stress distribution of the pipes under constant internal and external pressure are analyzed by using FEA software, respectively. The differences between the mechanical properties of the two kinds of composite pipes are elaborated by comparing the displacements of the distribution curve along their corresponding paths. The results show that the braided steel wire reinforced composite pipes have better mechanical properties than the welded ones. That may be due to the crisscross that makes both the clockwise and counter-clockwise steel wires bear the same pressure.

10

Authors: Kei Eguchi, Ichirou Oota, Shinya Terada, Hongbing Zhu

For back-lighting applications, a white LED (WLED) driver using a hybrid-input negative ring-type converter is proposed in this paper. To drive the LED’s cathode, the proposed driver offers the negative steppedup/stepped-down voltages by converting clean energy. The proposed driver can realize longer battery lifetime than conventional converters, because 1. In spite of the variation in clean energy input, the proposed step-up/step-down driver can utilize the clean energy effectively and 2. The proposed driver can charge a rechargeable battery when the back-light is standby mode. The properties of the proposed driver were clarified by theoretical analyses and SPICE simulations. SPICE simulations showed that the proposed driver can provide the sufficient voltage to drive LEDs by using not only battery energy but also clean energy. Furthermore, the theoretical formulas are useful for designing the proposed driver, because the theoretical results corresponded well with the simulation results.